antares vs celestron focal reducer antares vs celestron focal reducer

I have an 8SE, and am thinking about getting a focal reducer. Watch this before you buy Celestron 8SE SCT, or a Focal Reducer or a Hyperstar 7,758 views Mar 28, 2018 145 Dislike Share Ray's Astrophotography 42.3K subscribers Note: I am not paid or. Reducer Lens .7x - EdgeHD 1100. For example, many focal reducers designed for f/7 or f/8 ED refractors such as those from Tele Vue, William Optics, Sky-Watcher, and Meade are designed to have a working distance (or back focus) of 55mm. Perhaps not exactly- there will be some uncertainty because of manufacturing tolerances and so forth, but it will be close. JavaScript seems to be disabled in your browser. Besides observing from his heavily light polluted backyard in Los Angeles, Manish enjoys conducting astronomy outreach programs in local schools. 2023 OPT Telescopes. An eyepiece with a 27mm field stop yields a true field of 1.03 in the C6 at f/10. However, in principle, the reduction factor of a focal reducer can be varied by changing the distance from the back of the focal reducer to the camera or eyepiece. The Reduction Factor and the Amount of Reduction are inversely related. Some faster refractors with a focal ratio of f/6, for example, only require field flatteners and not focal reducers. Can these economical focal reducers from GSO and other vendors result in good images? All additional accessories mount onto the exterior/male threads. Most manufacturers provide this specification. The reducer fits all Meade and Celestron . To calculate how much back focus spacing you need to add, take the thickness of the filter and divide it by 3. And, the reality is that every F/6.3 RC out there Celestron, Hirsch, Astromania, etc., etc. No rainchecks will be issued for items out of stock at OPTcorp.com to match a competitor's price. The designed reduction factor (0.5x in the case of the GSO reducer example above) should be considered a rule of thumb or approximate value in most cases, rather than a very precise number. When using the diagonal, keep the field stops of the eyepieces under 20mm. During a twenty-year scientific career, he developed laser systems to detect molecules found in interstellar space and planetary atmospheres, and leveraged his expertise to create laser technology for optical communications networks. It also leads to larger (although fainter) images of extended objects like the Moon or planets for astrophotographers or visual observers. (Note: Using the simple equations above, the focal length of this reducer can be estimated to be about 350mm). Never noticed any anomalies with this unit. Years ago, I bought the Antares version, and moved over to the Celestron. Imagine having two telescopes in one a long focal length instrument for lunar and planetary work and a short focal length scope for deep sky observing and astrophotography. So it provides a 0.63x design reduction factor when used with an f/10 SCT at the specified working distance. This was most noticeable on the eyepiece end of the RC, where the metal rim surrounding the lens was about 1mm thicker than on the Celestron. There are also third-party vendors such as Hotech. Again, swapping back and forth for a couple of hours on M44, M35, and several brighter stars, I examined the shape of specific stars near the edge of the field with both correctors. Anyway, when purchased my R/C the "original" Celestron unit was not readily available and was offered instead the one sold under the shop's own label (in my case Tecnosky, but I saw the same product offered under TS label). No difference. I would not use the reducer with a 2" diagonal or eyepiece in the C6. It might work but it does not tell us anything about how well or to what extent the product works to correct the field of an SCT. Thanks for pointing this out. In some cases, focal reducers also act as field flatteners by correcting for field curvature and coma of the objective lens. Dedicated focal reducers for refractors are intended primarily for imaging, not visual observation. The equations and argument in the Appendix of this article shows the relationship between the working distance and the reduction factor. Like many of us with SCTs, I have bought and sold a number of f/6.3 reducer/correctors over the years, and I have always been curious how they really stack up to each other. Images made with my ZWO 533 camera testing both show them to be essentially the same. Meade does not make an equivalent line of focal reducers for the ACF scopes, although some models of Meade ACF are already at f/8, faster than the f/10 ratio of Celestron Edge HD scopes. Meade once made an f/3.3 focal reducer for SCT scopes. An f/6.3 reducer is designed to reduce the focal ratio of an f/10 SCT to f/6.3. Like you, I am primarily visually observing but I have everything together now that so I am going to start experimenting with photography so we'll see how it does there. Celestron Nexstar+ 127 SLT, several budget plossl eyepieces, Celestron 8-24mm zoom EP and a 12.5mm illuminated double reticle EP, Svbony SV205 camera w/.5 focal reducer, Celestron SkyMaster 20x80 binos on a 40 yr old QuickSet PanHead tripod, Stellarium, Sharpcap and ManyCam on my laptop, SkyView and Nightshift on my phone and a dandy little $9 . Unique focal reducer and field corrector lens accessory Reduces the focal length and f/ ratio of your Schmidt-Cassegrain telescope by 37% Provides a dual focal ratio instrument, without sacrificing image quality Compatible with all Schmidt-Cassegrain telescopes (see compatible list in description) Share Customers Also Purchased Description Sharpness is essentially the same. and you will be fine. For these items, please contact us to obtain a shipping quote before you check out using the online shopping cart.International Customers:Free shipping does not apply to international orders. Yellow and orange members of open clusters stood out a bit more as the various stars displayed their individuality. You need to be a member in order to leave a comment. If used with other f/ratios, the field flattening characteristic may be unpredictable. However, some focal reducers can be used over a wider range of working distances, especially those with simpler optical design, and especially when used with cameras with smaller sensors. We will be glad to help. High power views will provide flatter fields all the way to the edge, both visually and photographically. First, I wanted to compare the actual reduction provided by these competitors, as many threads here cite different ideal spacing from the reducer to eyepiece focal plane to achieve the correct f/6.3 result. This award-winning optical system reduces visual defects like field curvature and coma, creating an ultra-flat field for pinpoint stars all the way to the edge of todays largest imaging sensors. This rugged, 3-in-1 device features a true tactical 3-mode flashlight, a hand warmer, and a portable power bank for recharging your personal electronics on the go. We have tested our current batch and it works with Meade, Celestron, and Baader SCT accessories. Reducer Lens .7x - EdgeHD 1100 Learn More. 1.2" in that scope is a field stop of 43mm at f/10 and 27mm at f/6.3. I use the Celestron version and it seems OK for both visual and imaging. Assuming you use the reducer with the stock 1.25" diagonal, it will operate at f/6.3. Celestron is considered better in terms of QA, less likely to come with free dust, hair or fingerprint. Blue Fireball M42 T/T2 Thread Camera Adapter for Prime Focus Photography - 2" # P-06, Celestron T-Ring for Canon EOS Camera # 93419, GSO 2" Crayford Focuser for SCTs - Dual Speed, Length of male SCT thread = 5mm (0.2") but this is preceded by an unthreaded part on the eyepiece side making the total length = 8.8mm (0.35"), Length of female SCT thread = 7.5mm (0.3"). It's an either/or proposition: reducer and 1.25", or 2", but not 2" and reducer. Some coma is visible in the corners, but the image is quite good for EAA applications. The Celestron f/6.3 is ~150 compared to the Antares at ~70. This appendix summarizes how this works based on simple equations from the book Telescope Optics by Rutten and van Venrooij. I happily cycle through LRGB filters to build the image rather than do a whole run of one filter at a time. Focal reducers also move the effective focal plane of the objective inward, that is, towards the objective (see Figure 1). No idea what the issue is. However, some focal reducers can be used on other models of telescopes, but this is not always possible. Meade and Celestron both sell such SCT-T adapters with the correct optical length. control and Sky Viewer display makes selecting your target easy. The most commonly available focal reducers for SCTs are the f/6.3 reducers from Celestron and a similar f/6.3 focal reducer from Meade. Using one on such a scope would make demands on the eyepiece design and increase the exit pupil to an extent that focal reduction on fast Newts is not practical. Not noticed any optical problems. When placed in the focal plane in front of a camera or eyepiece, a focal reducer leads to a wider field of view and a brighter image of extended objects, which is important for reducing the exposure times when imaging faint extended objects like nebulae or galaxies. Normal shipments will resume on Monday, March 6, 2023. nleash the full pointing accuracy of your Celestron computerized telescope with a specialized telescope control software suite. Thks for that and its not for visual it for astrophotography. You currently have javascript disabled. If you want to save a few buck watch the classifieds on CN. That said any comparison reviews are helpful. Brian Ventrudo is a writer, scientist, and astronomy educator. It seems right to put some distance between the camera and the focal reducer, right? They are designed (assuming you are referring to the f/6.3 version) for the f/10 light cone. As per the OP I still can't see any reason to buy the Celestron for significantly more $$$. All Rights Reserved. However, even though the imprint on the item states "Reducer / Corrector" please note that his is a reducer only. The focal length of a focal reducer is usually measured from the rear lens surface of the reducer (and not the reducer's housing). This superb fully multi-coated multi-element focal reducer takes advantage of the latest computer aided design techniques to achieve the highest standards of performance set by the brand leaders at a fraction of the cost. The focus barely shifts between filters and I suspect any shifts I do get are down to the filters and changes in temp. Benefits limited to hardware and conditions? But nearly every observer who installs one of these devices is pleased with their performance. looks virtually identical, except for the lettering. During checkout, you may also be shown other optional faster shipping choices.US Customers in Hawaii and Alaska: Free shipping applies to almost all products. Bear in mind you can't squeeze blood out of a turnip, i.e. Please let us know what topics you are interested in. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. WiFi technology encircles the globe in a web of connectivity, knowledge, and information. For Stephen Wilkerson: The ZWO ASI120MC-S does come with a wide angle lens, HOWEVER, it is NOT intended to used when you are using the ASI120 camera attached to your telescope. The distances d1 andd2 can also be expressed in terms of the focal length of the focal reducer FR with the lens equation: Using Equation 2, Equation 1 can also be expressed in terms of d2: The focal reduction factor of the focal reducer depends on its focal length and its distance from the focal plane of the objective as shown by Equation 4: Again, for example, when the focal reducer is placed at the original focal plane of the objective, d1=0 and MR=1, which means there is no focal reduction. Because most modern Newtonians already have relatively fast focal ratios, these telescopes do not usually use focal reducers. Focal reducers for these relatively fast ED refractors are generally for imaging only, not for visual observation. It's usually specified in millimeters. How does it look thats what matters. The distance d2, which measures the position of the new focal plane of the objective from the back of the focal reducer is given by Equation 5: In these equations, d1, d2, and MR are all variables that depend on each other through Equations 2 and 4. Add a 0.63x reducer, and the brightness of extended objects increases by (1/0.63)2 = 2.5. But is there a difference in quality between the Antares and the Celestron or Meade focal reducers? This focal reducer is made to attach to the rear cell of Schmidt-Cassegrain or Maksutov-Cassegrain telescopes. The Best Dedicated Astronomy Cameras for Beginners, Astronomik OIII 12nm CCD Filter - T-Threads, Pegasus Astro Dual Motor Focus Controller, 10 Micron 12kg (26.45lbs) Stainless Steel Counterweight- GM 2000, I would like more information regarding stock availability dates. More details are found in the Appendix of this article. Have a promo code? The working distance or required back focus, explained above, is usually specified and is far more important in practice. ED stands for "extra-low dispersion," which refers to the composition and optical properties of the glass used for the lenses. Many reducers, such as the Celestron HD focal reducer mentioned above, and many focal reducers for apochromatic refractors, are meant to be used within a few millimeters (or less) of the specified working distance to achieve the best possible image results. Figure 7 shows an example of an image of the Dumbbell Nebula taken with a 1.25" GSO focal reducer at a reduction factor of 0.63x with an 85mm f/7 refractor and a QHY5III-290M camera with a sensor with a 6.4mm diagonal. Many focal reducers for refractors have a working distance (or back focus distance) of 55mm. We do not price match competitors if they are out of stock. I have the Antares and am not unhappy with it, but for AP I would want more back focal distance if those numbers are accurate. Clearly cost is a big factor for satisfied users. These scopes are compatibles with focal reducers. Explore Scientific Keys to the Universe Sale, Antares f/6.3 Focal Reducer for Schmidt-Cassegrain Telescopes, Skip to the beginning of the images gallery. Celestron's EdgeHD reducers feature a custom 5 element optical design engineered to maintain the flat-field performance of our award-winning EdgeHD optical system. This may be a problem if the focuser tube or the diagonal (for visual observing) is too narrow to accept light at this larger angle. The most significant mechanical variation, however, is the quality and precision of the threading. Planetarium software package which provides easy-to-understand explanations and impressive visuals of all kinds. I wish there was. Since 2008, Brian has taught astronomy to tens of thousands of stargazers through his websites OneMinuteAstronomer.com and CosmicPursuits.com. I think that the FRs made in Japan in the day may have been better. Read our guide! You may need spacers or a T-adapter to ensure the correcting working distance. If the focal reducer is to be used for visual observation, the visual back is threaded onto the eyepiece side of the reducer, and then a star diagonal and eyepiece are installed as usual. Contiguous US Customers:All items we sell ship for free within the Contiguous US. Some third-party vendors also make reducers for SCT scopes. Thank you so much for the informative article, I now understand better how to integrate my reducer into my system to get better performance. Celestron or Antares? They are commonly available in 1.25" and 2" threaded cells that conveniently thread into the nosepiece of a compatible camera or the barrel of an eyepiece. This would tell us exactly how well aberrations are corrected. Housings, threads, reduction, correction, blah, blah, blah. They are reported as identical. Oceanside Photo & Telescope wants our customers to shop with confidence knowing that you will always get the best deal available. It threads onto the rear cell of 5" to 16" Celestron and Meade Schmidt-Cassegrain telescopes, making it possible to have a dual focal ratio instrument without sacrificing image quality. Unlike . Product Details. Is that distance D= Fo-d1=Fo-(d2/MR)? I have/had both the Celestron (Japan) and Antares units. Celestrons award-winning Nature DX binocular gets a major upgrade with the addition of ED objective lenses. This focal reducer and field flattener consists of a four-element multicoated 40mm lens in a metal cell. No negative issues to report. A couple of tiny dust particles between lens elements, uneven lens edge blackening, very minor coating blemishes, or even a very small fine lens scratch or two are very common in this Antares product and must be accepted as normal for this item. It is not a corrector or flattener. The equations in the Appendix show how this all works. For me, I was looking for, and planning to keep, the one that yielded the greatest reduction. https://www.celestron.com/products/reducer-corrector, //cdn.shopify.com/s/files/1/1935/4371/products/94175_reducer_corrector_01.jpg?v=1603736883, //cdn.shopify.com/s/files/1/1935/4371/products/94175_reducer_corrector_01_medium.jpg?v=1603736883, Popular Science by Celestron StarSense Explorer DX 5" Smartphone App-Enabled Schmidt Cassegrain Telescope, Advanced VX 8" Schmidt-Cassegrain Telescope, C9.25 Optical Tube Assembly (CGE Dovetail), Advanced VX 6" Schmidt-Cassegrain Telescope, Advanced VX 700 Maksutov Cassegrain Telescope, CGX-L Equatorial 925 Schmidt-Cassegrain Telescope, CPC 1100 GPS (XLT) Computerized Telescope, CGX-L Equatorial 1400 Schmidt-Cassegrain Telescope, CGX-L Equatorial 1100 Schmidt-Cassegrain Telescope, CGX Equatorial 925 Schmidt-Cassegrain Telescope, CGX Equatorial 800 Schmidt-Cassegrain Telescope, CGX Equatorial 1100 Schmidt-Cassegrain Telescope, CGEM II 1100 Schmidt-Cassegrain Telescope, Advanced VX 9.25" Schmidt-Cassegrain Telescope, Advanced VX 11" Schmidt-Cassegrain Telescope, Not compatible with #93648 Off-Axis Guider, not compatible with #93519 2" Mirror Diagonal (discontinued), Currently not compatible due to mechanical interferences. If you place your camera at a different working distance, you will get a different reduction factor and perhaps unwanted distortion in the image. Focal reducers for refractors with focal ratio of f/7 to f/9, roughly, have a design reduction factor of about 0.75x to 0.8x and produce a flat field by correcting for the curvature of the objective lens. It was also a little brighter in the center of the field with subtle darkening in the outer 20% or so. Orders placed after 12:00 PM Pacific Time will be shipped the next business day. What I do know is that the Antares and the Celestron samples that I have perform exactly the same from the center right out to the edges. Field stop diameters are one of the specified specs of eyepieces. I was originally hoping to do this with a made in Japan Celestron, but ended up with a newer China version but thats probably better in the end since it is the version now available, with the Japan ones rarer and only available used. Many Ritchey-Chretien telescopes available today are made by GSO. Thanks for any advice or experience you could share. - thanks. The faster f/ratio allows you to use slower film or shoot in lower light level situations and still properly expose your subject. Both exhibited consistent reduction, identical field flattening, and edge correction properties, and both were high quality optically and mechanically. Sign up for a new account in our community. Once installed, you can add additional accessories like T-Adapters, 1.25 Visual Back, Star Diagonal, or Off-Axis Guider. We will match any online price that we confirm as valid. For this shoot-out, I used a standard Celestron C8 with Starbright coatings. Copyright 2003-2022 Agena AstroProducts. The most popular accessories for your new telescope! This telescope control software replaces the hand control and allows the user to remotely control their Celestron computerized telescope from their personal PC or laptop. Wonder how they would stack up with a Japanese 6.3. a Tele Vue Panoptic), or a Plossl eyepiece with an apparent field of view of 50 and a focal length of 32mm. Celestron Solar Safe filter technology is GUARANTEED SAFE for direct solar observation and has been independently tested by SAI Global Assurance Services. This factor is designated by a power that is less than 1, and it usually lies between 0.5x or 0.8x. Does anyone know if the Antares 4000 focal reducer is as good as the Celestron focal reducer. My application is mostly visual now, but I'm looking to do more astrophotography over time. In these equations: The combined focal length of the objective and focal reducer is given by Equation 1: For example, when d1=0, that is, the focal reducer is at the focal plane of the objective, Fcomb=Fo, so the focal reducer has no effect. You also wont be unhappy spending the few extra bucks on the Celestron for the pretty orange lettering, particularly if you can pick one up used, as I did. Also, the focusers of most Newtonians do not have enough in-travel to accommodate a focal reducer. I really don't see any difference in the current crop except the "Meade" is usually the cheapest. Your eyepieces are the first accessories you should learn to use with your telescope. Just one question. ED glass is specially formulated and contains rare-earth compounds that greatly reduce a visual defect called chromatic aberration. If used before or beyond the working distance, unwanted image distortion may result. USD $80.00. Again, these focal reducers are often provided by the telescope manufacturer. You cannot, for example, use a 0.63x focal reducer intended for a standard Celestron or Meade SCT and use it on a Celestron Edge HD or a Meade ACF. Antares' f/6.3 focal reducer provides a faster f/6.3 system for imaging or visual use when used with an f/10 SCT or other compatible telescopes. Therefore, a 55mm back focus with a filter that is 3mm thick added to the imaging train would become 56mm. All rights reserved. Reducer Lens .7x - EdgeHD 1400 Learn More. Celestron or Antares f/6.3 focal reducer for SCT? I'd favor the Japanese Celestron version over the others that are commercially available. I own both and concur heartily. Reducer Lens .7x - EdgeHD 800 For imaging, a T-adapter is threaded to the camera side of the focal reducer, which in turns connects to the camera with the appropriate hardware. He received his first telescope at the age of 5 and completed his first university course in astronomy at the age of 12, eventually receiving a master's degree in the subject. This is the simplest way to attach your ASI121 to your telescope. This focal reducer is made to attach to the rear cell of Schmidt-Cassegrain or Maksutov-Cassegrain telescopes. Check out our 2022 telescope buying guide here! I've only used it a few times but it looks good to me. Some refractors such the TeleVue Nagler-Petzval (NP), the Takahashi "FSQ", and the William Optics Redcat/WhiteCat 51 have inherently flat fields because of internal optical elements. Great report and verifies what I had thought all along, Fortunately, my neighbors are not out in their backyards at 11 pm, or they may have thought I was torturing a small mammal. Reducer Lens .7x - EdgeHD 925 Learn More. Using an eyepiece with a 27mm field stop with the reducer will illuminate the edge the same as using an eyepieces with a 42.9mm field stop without it. To further factor out my natural astigmatism (I normally wear glasses while observing), I did the tests with my regular progressive lenses, single vision glasses I use when observing, and naked eye. None of this was offensive, nor did it interfere with views in any significant way. JavaScript seems to be disabled in your browser. The more focal reduction, the further inward the focal plane will be. Stock focusers in an SCT move the mirror of the scope to change the position of the focal plane, and they have sufficient travel to accommodate a focal reducer. control and Sky Viewer display makes selecting your target easy. In this case, an additional T-adapter (with an optical length of 50mm) is needed to get the spacing correct for a DSLR or other camera with a 55mm back focus. Sign up to receive sale alerts, news about upcoming celestial events, and telescope tips from our experts! Community Forum Software by IP.BoardLicensed to: Cloudy Nights, E of San Francisco Bay and W of the Awahnee, This is not recommended for shared computers, reviews here that suggest a coating problem, Back to Celestron Computerized Telescopes, Looking for advice on first refractor and camera. In some cases, focal reducers also act as field flatteners by correcting for field curvature and coma of the objective lens. F6.3 Focal reducer for F/10 or higher telescopes, 43mm aperture, 4-Element, Fully Multicoated. The resultant reduction factor was measured to be 0.46x. More important, its clear that the Antares is a reducer/corrector, just like the Celestron and not merely a reducer. Using this same example of an 8" SCT and a 0.63x reducer, a visual observer can also enjoy brighter images and a wider field of view. Telescope Optics, Rutten and van Venrooij, Chapter 15, Willman-Bell (1988). It was used strictly for imaging, not visual observing. which looks like the same one. Best evidence would by obtained by using a camera and evaluating the image both by eye and with a computer analysis. A former wireless communications consulting engineer and management consultant to various Fortune 500 companies, Manish started Agena AstroProducts in 2003. As mentioned in Section 2.3, the reduction factor for these focal reducers can be varied by adding spacers to move the reducer further from the camera sensor or eyepiece. The visual back must be removed first. DUE TO EXTREMELY HIGH DEMAND, WE WILL NOT BE TAKING NEW ORDERS UNTIL MONDAY, DECEMBER 14. The naming convention of SCT focal reducers is a little confusing. Figure 1 shows the relationship between the focal reduction factor MR and the position of the reducer in the optical path. Learn more about extra solar planets imagery, 3D Star rendering, observation planning, telescope control, multiple-panel printing, and much more. Maybe I got a lemon. Reducer Lens .7x - EdgeHD 800 Learn More.